6b ... I just dont get it .. 6a is 32,458 taxable income But 6b it is a 0.00 ... Is this a glitch?

 

Yikes.  This year my Taxable Social Sec. Benefits for 2024 (6b) is 0.00 (down from $20,455 last year)

 

Last year ('23) 6a was $32,458 and 6b (taxable portion) was $20,455

This year ('24) 6a is $33,488 and 6b shows at $0.00 

How can that be?  Is this a software glitch?  Shouldn't this year's 6b be similar to last year?

Thanks much to help me understand this... im making sure its not a mistake to go ahead and file.